Directions: This part is to test you listening ability. It consists of 3 sections Section a: Conversations Directions: In this section, you will hear 10 short conversations. At the end of each mersation, a question will be asked about what was said. Both the conversations and the questions will be spoken only ONCE. After each question there will be a pause During the pause, you must read the four choices marked A), B), C) and D), and decide
第一节 崩塌 6.1 Collapse 6.1.1 Types of collapse 6.1.2 Forming conditions of collapse 6.1.3 Accumulation and landforms of collapse 第二节 滑坡 6.2 Landslide 6.2.1 The shape of a landslide 6.2.2 Influence factors to a landslide 6.2.3 Types of a landslide 6.2.4 The development of a landslide 6.2.5 Prevention of a landslide
1、解: (1) P{只订购 A 的}=P{A(B∪C)}=P(A)-{P(AB)+P(AC)-P(ABC)}=0.45-0.1.-0.08+0.03=0.30. (2) P{只订购 A 及 B 的}=P{AB}-C}=P(AB)-P(ABC)=0.10-0.03=0.07 (3) P{只订购 A 的}=0.30